Speaking of rigging tension...

Feb 5, 2009
255
Gloucester 20 Kanawha River, Winfield, WV
Here's what my boat's manual says on the subject: "The forestay and backstay should be carried quite snug. The tension between the upper and lower side stays, or shrouds, should be adjusted so the mast is straight athwartships when sailing in a good breeze. In general, the shrouds should always be kept rather taut, but they do not have to be exceptionally tight." Anybody know where I can get a gauge calibrated from rather taut through quite snug to exceptionally tight?
 
Jan 11, 2014
13,998
Sabre 362 113 Fair Haven, NY
Hmmm. Frederick’s of Hollywood?
Are they still in business?

Anybody know where I can get a gauge calibrated from rather taut through quite snug to exceptionally tight?
A small Loos gauge should work well on the Gloucester 20. As a rough gauge, if the shroud is only hand tight, then it is too loose. On a gauge, the tension should be between 10 and 15% of the breaking strength of the wire. Below 10% and you're probably too loose above 15% you are too tight. The best tension is going to vary depending on wind and sea conditions, in lighter air tend towards the lower rating, in higher winds tend towards the upper rating.

Over tensioning the rig induces too much tension in the boat and puts too much pressure on the mast step, chain plates, and bulkheads. Too little tension and the rig is subject to shock loading, especially in choppy water and gusty conditions. The loose shroud allows the mast to move too much and gain too much speed before the shroud stops the mast. Sort of like jerking a line versus applying steady pressure.
 
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Feb 5, 2009
255
Gloucester 20 Kanawha River, Winfield, WV
A small Loos gauge should work well on the Gloucester 20.
I'm hoping to get one of those before I replace any more of my rigging. Except for the backstay, I'm using all the original 31 year-old wires with turnbuckles that look like they belong on lifelines. (Before anyone chastises me for risky behavior, bear in mind that I have a small boat confined to an inland river and my excursions seldom coincide with the wind blowing.)
 
Jan 11, 2014
13,998
Sabre 362 113 Fair Haven, NY
I'm hoping to get one of those before I replace any more of my rigging. Except for the backstay, I'm using all the original 31 year-old wires with turnbuckles that look like they belong on lifelines. (Before anyone chastises me for risky behavior, bear in mind that I have a small boat confined to an inland river and my excursions seldom coincide with the wind blowing.)
The good news is if the boat has always been on freshwater, the rigging is probably still in pretty good shape. Your boat is small and light with a small sail plan. The rigging will match the size of the boat, I would not be surprised if the rigging is the same size as or smaller than lifeline rigging.

Check with RiggingOnly.com they may have the specs for your boat.
 

jviss

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Feb 5, 2004
7,090
Tartan 3800 20 Westport, MA
If you use a Loos gauge, note that the percent breaking strength marked on the gauge only applies to type 302 and 304 stainless steel, not the type 316 that Rigging Only uses. The tension numbers are still good.
 
Jul 7, 2004
8,534
Hunter 30T Cheney, KS
I'm hoping to get one of those before I replace any more of my rigging. Except for the backstay, I'm using all the original 31 year-old wires with turnbuckles that look like they belong on lifelines. (Before anyone chastises me for risky behavior, bear in mind that I have a small boat confined to an inland river and my excursions seldom coincide with the wind blowing.)
I have to use 2 Loos gauges now. The one for my old Mac only fits my backstay now. Had to go to the next model for the side shrouds.
 
Jan 11, 2014
13,998
Sabre 362 113 Fair Haven, NY
I have to use 2 Loos gauges now. The one for my old Mac only fits my backstay now. Had to go to the next model for the side shrouds.
I hear ya! I now have 3 Loos gauges, one in each size. The small gauge that fit my Sabre 30, the next 2 for the different size shrouds on my 362.